Since the amount of solar energy is limitless, it is inexhaustible and entails little environmental pollution. Research into the conversion of solar energy into electrical energy is underway due to these characteristics of solar energy.
A solar battery has been used as a method of converting solar energy into electrical energy since the 1980s. A solar battery is a photocell which is produced with the aim of converting solar energy into electrical energy. A solar battery can be broadly divided into ‘a solar thermal cell’ and ‘a photocell’. While the solar thermal battery is a device that uses solar thermal energy to generate steam, which is needed to rotate a turbine, the photocell is a device for converting the sunlight into electrical energy using the characteristics of the semiconductor. The intensity of research and development pertaining to photocells has increased recently.
The first material used in preparing solar batteries is single-crystal silicon. Although the relative importance of the solar battery in the marketplace has been low, these days its market importance is increasing, especially in the large-scale generating system field. That is why the conversion efficiency of solar batteries made from single-crystal silicon is much higher than that of other solar batteries made from other materials.
However, if a solar battery is prepared from single-crystal silicon, it entails some problems, such as the high cost of production, a complicated process, etc. To solve these problems, there have been attempts to prepare a solar battery from organic materials. If a solar battery is prepared from organic materials, the cost of production can be lowered and mass production on an industrial scale is possible. Moreover, if organic material is used as a raw material, there are advantages in that the weight is reduced and thus the battery is simple and convenient. Further, since organic material is flexible, unlike inorganic material, the shape of the battery is not limited, and can be widely applied in various fields.
However, if a solar battery is prepared from organic material, it has a problem in that the photovoltaic conversion efficiency, that is, energy conversion efficiency, is lower than that of the battery made of silicon. Further, if a solar battery is prepared from organic material, the yield of the target product must be raised to increase productivity, and mass production is needed in order to reduce production costs.